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3) ZHH Subgroup (Reported by T.Suehara)
Status:
- Observation:
b-tagging essential to BG reduction
current b-tagging scheme, which does b-tagging after jet clustering,
often mis-assign particles from a single b-hadron to different jets.
-> We should do the vertex finding before jet clustering.
- Developed new jet clustering along this line.
- Preparatory study with this new jet clustering
--> 30% improvement in ttbar BG reduction
Next step:
- Optimization of flavor tagging for multi-jets
- Realistic ZHH analysis with new algorithms

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The slides shown at the meeting is available from
http://ilcphys.kek.jp/meeting/physics/
see them for details.
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